Top Level API

Here are all the functions you call to control the operation of WebGazer.

• on include of script in body
• webgazer namespace object introduced
• overwrites any other webgazer data to prevent data contention
• webgazer singleton namespace object
• control functions
  • webgazer begin()
    • begins collecting click data and activates the camera, should be called as soon as possible to improve accuracy
    • attaches window click listener
    • starts clock
    • video div attached to body
      • id = webgazerVideoFeed
      • style = invisible
    • canvas attached to body
      • id = webgazerCanvas
      • style = invisible
    • returns webgazer object
  • webgazer pause()
    • stops all webgazer data collection and predictions
    • returns webgazer object
  • webgazer resume()
    • resumes all webgazer data collection and predictions after a pause()
    • returns webgazer object
  • webgazer end()
    • stops all webgazer data collection and predictions and releases all memory being held by the webgazer object.
    • Accuracy may suffer if begin is called afterward, consider using pause and resume instead
    • IMPORTANT: saves global model data so that user’s returning to the page will have a pre-loaded model
    • returns webgazer object
  • webgazer showPredictionPoints(boolean)
    • if bool is true: shows a circle with the current best guess given by the prediction model
    • if bool is false: turns off the prediction circle
    • returns webgazer object
  • boolean detectCompatibility()
    • tests for certain browser requirements that webgazer depends on
    • checked again in begin() //TODO
    • returns true if browser meets expectations, false otherwise
• setters
  • webgazer setTracker( libraryString )
    • sets which facial recognition library webgazer should use
    • libraryString - a string corresponding to one of the following
      • ‘clmtrackr’
      • ‘js_objectdetect’
      • ‘trackingjs’
    • returns webgazer object
  • webgazer setRegression( regressionString )
    • sets which regression model type webgazer should use
    • regressionString - a string corresponding to one of the following
      • ‘ridge’
      • ‘linear’
      • ‘interaction’
    • returns webgazer object
  • webgazer setGazeListener( callback )
    • sets a callback which will be invoked every time webgazer makes a new prediction
    • only one callback can be registered at a time, so in multiple calls to setGazeListener only the last callback will remain registered
    • callback - function(gazeData, elapsedTime) //TODO this has changed to include results of all regression models
      • gazeData - object or null if prediction failed
        • x - predicted gaze x screen coordinate in pixels
        • y - predicted gaze y screen coordinate in pixels
      • elapsedTime - time in milliseconds since begin() was invoked
    • returns webgazer object
  • webgazer clearGazeListener()
    • removes the current callback
    • use this method instead of pause/resume when data should continue to be collected to improve the accuracy
    • returns webgazer object
• getters
  • string getTracker()
    • gets the current facial recognition library
    • returns string - the string corresponding to the library
  • getRegression()
    • gets the current regression model type
    • returns string - the string corresponding to the regression model
  • {x:, y:} getCurrentPrediction()
    • request a prediction from webgazer
    • returns object or null
      • x - predicted gaze x screen coordinate in pixels
      • y - predicted gaze y screen coordinate in pixels